Research efforts will continue to be directed toward elucidating eukaryote chromatin structure using micrococcal nuclease digestion kinetics, chemical crosslinking, gel electrophoresis and potentially x-ray diffraction. Special emphasis will be placed on demonstrating the usefulness of micrococcal nuclease digestion kinetics as a probe of higher order chromatin superstructure by establishing between the kinetic behavior (described by log kcat and km) of various chromatin substrates and their appearance in the electron microscope. Two approaches of particular interest are to prepare oligonucleosome fragments without destroying "native" digestion behavior, and to reconstitute "native" digestion behavior from extended oligonucleosomes.